Feat/metrics exporter (#17)

Author: danimhr

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "pythnet-watcher"
-version = "1.0.0"
+version = "1.1.0"
 edition = "2021"
 
 [dependencies]
@@ -29,6 +29,10 @@ tokio-stream = "0.1.17"
 tracing = "0.1.41"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter", "json"] }
 wormhole-vaas-serde = "0.1.0"
+axum = "0.8.4"
+metrics = "0.24.2"
+lazy_static = "1.5.0"
+axum-prometheus = "0.9.0"
 
 [dev-dependencies]
 serde_json = "1.0.140"

Cargo.toml

@@ -84,3 +84,10 @@ This will save the key in raw byte format to the file named `.secret`.
 ### 🧪 Testing Locally
 
 To test in a non-production environment (e.g. with devnet or a local Pythnet fork), just provide a different `--pythnet-url`, and `--server-url`, and optionally use custom `--wormhole-pid`.
+
+---
+
+### 📊 Metrics
+
+By default, running the watcher exposes metrics at `http://127.0.0.1:9001`.
+You can change the metrics endpoint by passing the `--metrics-addr` flag or setting the `METRICS_ADDR` environment variable.